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%I #8 Oct 21 2018 17:10:45
%S 81,245,777,2597,8961,31837,115561,427093,1600465,6064925,23183481,
%T 89239333,345404641,1342911981,5240253833,20510674037,80485531761,
%U 316523691581,1247135002521,4921936192325,19452979579137,76982463799693
%N Number of (n+1) X (1+1) 0..2 arrays with the maximum plus the minimum minus the upper median minus the lower median of every 2 X 2 subblock equal.
%H R. H. Hardin, <a href="/A237160/b237160.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) + 2*a(n-2) - 92*a(n-3) + 80*a(n-4) + 376*a(n-5) - 360*a(n-6) - 600*a(n-7) + 400*a(n-8) + 320*a(n-9).
%F Empirical g.f.: x*(81 - 322*x - 1100*x^2 + 4120*x^3 + 5288*x^4 - 14656*x^5 - 11416*x^6 + 15792*x^7 + 9664*x^8) / ((1 - 4*x)*(1 - 2*x^2)*(1 - 3*x - 2*x^2)*(1 - 10*x^2 + 20*x^4)). - _Colin Barker_, Oct 21 2018
%e Some solutions for n=5:
%e ..0..1....2..1....2..1....2..1....1..0....1..0....1..2....2..2....0..2....1..1
%e ..2..1....1..0....2..1....1..0....1..2....1..2....1..2....1..1....0..2....2..0
%e ..0..1....1..2....0..1....0..1....0..1....0..1....1..0....1..1....0..2....0..2
%e ..1..2....0..1....1..2....1..2....1..2....2..1....2..1....2..2....0..2....0..2
%e ..1..0....0..1....0..1....1..0....2..1....2..1....0..1....0..0....2..0....1..1
%e ..1..0....1..0....0..1....2..1....0..1....1..0....1..2....1..1....2..0....1..1
%Y Column 1 of A237167.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 04 2014
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